1. Field of the Invention
The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus for performing feed forward control.
2. Description of the Related Art
There has been already known a technique that counts pixels forming a toner image and performs feed forward control on the amount of replenished toner or the amounts of heat and pressure on fixing based on the count value (the number of pixels) in an image forming apparatus such as laser printer, facsimile, and digital copying machine. With the technique, conventionally a count value of print image data by one page of transfer sheet is acquired to perform feed forward control. Recently, in order to execute real-time control, the print image data by one page of transfer sheet is divided into fine regions, and a count value is acquired per divided region to perform feed forward control.
In this respect, Japanese Patent Application Laid-open No. 2010-015018 discloses an image forming apparatus that divides print image data by one page of transfer sheet into a plurality of blocks, and supplies a proper amount of toner to developing units based on density data calculated for each block.
However, when there is employed the structure in which the print image data by one page of transfer sheet is divided into fine regions to acquire count values, there is a problem that CPU calculation loads increase along with the short forward control loop.
Therefore, there is a need for a novel image forming apparatus capable of reducing CPU loads in the image forming apparatus that performs feed forward control at a high frequency.